Large-scale mapping of parameters of multi-dimensional structures in natural environments

• US 5,555,018 A
• Filed: 07/05/1994
• Issued: 09/10/1996
• Est. Priority Date: 04/25/1991
• Status: Expired due to Fees

• Current Assignee: Heiko S. Von Braun
• Original Assignee: Heiko S. Von Braun
• Inventors: von Braun, Heiko S.
• Primary Examiner(s): Britton, Howard W.
• Application Number:
  US08/270,421
• Time in Patent Office: 798 Days
• Field of Search: 348/144, 348/147
• US Class Current: 348/144
• CPC Class Codes: G01C 11/025 by scanning the object
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

Method for the large-scale mapping of parameters of multi-dimensional structures in natural environments or ranges. According to the invention, the range to be subjected to mapping or sections thereof are detected during first picture-taking flights at flight altitudes between about 150 m to 500 m above ground by means of series aerial surveying pictures taken by reconnaissance cameras (2) in combination with tele-cameras (3) for making detailed images from the range section covered by said reconnaissance cameras 2. The series aerial surveying pictures are set with respect to their position in the range by means of orientation aids and evaluated using photogrammetric techniques. The range data obtained of a structure are assigned to the coordinates of the structure in the range for selective retrieval.

Claims

1. A method for the large-scale mapping of parameters of multidimensional structures in natural environments, characterized in that the natural environment or range to be mapped or sections thereof are detected during first picture-taking flights at a flight altitude between about 150 and 500 m above ground by means of series aerial surveying pictures taken by reconnaissance cameras (2) in combination with tele-cameras (3) for making detailed images from the range section covered by said reconnaissance cameras (2), the series aerial surveying pictures are set with respect to their position in said range by means of orientation aids and evaluated using photogrammetric techniques, and the range data obtained of a structure are assigned to the coordinates of the structure in the range for selective retrieval.

2. The method according to claim 1, characterized in that the orientation aids consist of radio position determinations during the picture-taking flight which are triggered with the image-taking instants.

3. The method according to claim 1, characterized in that the tele-camera (3) is guided either automatically in accordance with a flight schedule using computer control, or free-handed by an operator.

4. The method according to claim 1, characterized in that during second picture-taking flights at flight altitudes of about 50 m above ground and at imaging scales of 1:

500 and less surveying picture orientation series are taken by means of a reconnaissance camera (2), and individual structures are taken from several directions from above and from the side.

5. The method according to claim 1, characterized in that the photographic pictures are taken with black-and-white films.

6. The method according to claim 1, characterized in that, in time-fixed correlation, pictures of sections of the range are taken by means of different photographic cameras in a vertically downwardly and obliquely downwardly inclined fashion and substantially transversely of the direction of flight.

7. The method according to claim 1, characterized in that control of the flight track (FT) of the first and second picture-taking flights, respectively, and/or of adjustment of the laterally oriented cameras (2, 3) to a predetermined section of the range is effected via a video camera (4) oriented in the direction of flight (FR), said video camera having a display screen on which the vertical projection of the flight track (10), which is executed in the direction of flight, and orientation lines (11, 12) indicating the adjustment of the photographic cameras (2, 3) are overlapping the video picture taken.

8. The method according to claim 1, characterized in that two laterally oriented photographic cameras (2, 3) are used, one of which (2) is a wide-angle camera.

9. The method according to claim 1, characterized in that the orientation aids consist of series aerial surveying pictures taken with the conventional aerophotogrammetric techniques and oriented in the Gauss-Kr uger net.

10. The method according to claim 9, characterized in that the series aerial surveying pictures are taken with vertically downwardly directed series surveying cameras (1) using an imaging scale of 1:

2000 and less, and in that the image-taking instants of said series surveying cameras are triggered with those of the reconnaissance cameras (2) and the tele-camera (3), respectively, and optionally of a video camera (4), and with a picture-taking flight anlayzer.

11. The method according to claim 10, characterized in that a black-and-white film having an increased infrared sensitivity or an increased sensitivity for blue is used.

12. A photographic surveying camera arrangement in a photographic aircraft, in particular for taking the aerial photographs according to claim 1, comprising at least one first series surveying camera (1) directed vertically downwardly, characterized by at least one second surveying camera (2) oriented substantially transversely of the direction of flight obliquely downwardly, and by a video camera (4) provided in the direction of flight, into the display screen of which the flight track (FT, 10) and the orientation (11) projected in the direction of flight of the second surveying camera (2) are cross-faded, with the instants of image triggering of the first (1) and second (2) camera standing in a fixed time relation.

13. The arrangement according to claim 12, characterized in that a third surveying camera (3) oriented substantially vertically of the direction of flight and obliquely downwardly is provided, which is equipped with a telephoto lens, the second surveying camera (2) comprising a wide-angle lens for covering a larger section of the range.

14. The arrangement according to claim 12, characterized in that the image sequence frequency of the second and third surveying camera (2, 3), respectively, and the camera adjustments thereof are controlled via a distance meter oriented in the picture-taking direction of the cameras, coupled with the flying speed.

15. A method for large scale mapping of parameters of multidimensional structures located in natural environments, using wide angle stereo aerial photography, the method being characterized by the steps of:

a) photographing at least sections of a range of a natural environment to be mapped with a wide-angle reconnaissance camera during picture-taking flights, the wide-angle reconnaissance camera being inclined diagonally downward with respect to an axis of flight to produce a series of aerial survey pictures showing the sections,

b) during the same picture taking flights photographing using a tele-reconnaissance camera inclined diagonally downward to make detailed images of at least portions to the sections shown in the series of aerial survey pictures, the detailed images showing in detail multidimensional structures located in said portions so that parameters of said structures may be determined therefrom,

c) scanning said section of a range to be mapped with a laser assembly comprising a group of laser units arranged with an equiangular distance in a line perpendicular to the flight direction to cover the width of said section with equidistant measuring points with a frequency dependent on the flight speed to get a series of measuring points approximately every 15 cm in flight direction,

d) combining the resultant surface profile data obtained by said laser scanning with radio position determination data (DGPS), and

e) orienting said series of aerial survey pictures in the net of measuring points obtained by said laser scan by comparing details on said laser scan with those on said images.

16. A method according to claim 15, wherein each laser unit emits a differently coded laser signal.

17. A method according to claim 15, wherein the radio position determination is carried out by a ground transponder.

18. A method according to claim 15, wherein the sampling frequency of the laser units is between 200 and 1500 Hz.

19. A method according to claim 15, wherein 32 laser units are arranged with a respective angle of 1°

between adjacent units.

20. A method according to claim 15, wherein the flight altitude is between 0 and 2500 m.

21. A method according to claim 15, wherein the flight altitude is between 0 and 565 m.

22. A method according to claim 15, wherein said wide-angle reconnaissance camera and/or said tele-reconnaissance camera are high resolution video cameras, respectively.